Method of making nut blanks



Oct. 27, 1931. PRAYER ET AL 1,829,558

METHOD OF MAKING NUT BLANKS Filed June 27. 1930 37 /|\NVENTOR5 BY M25. 7

ATTO RN EYB Patented Oct. 27, 1931 UNITED. STATES PATENT OFFICE LEE A. FRAYER AND CARL L. HARVEY, F KENT, OHIO, ASSIGNORS TO ROY H. SMITH, 0F KENT, OHIO METHOD OF MAKING NUT lBIL-ANIKS Application filed June 27,

This invention relates to a method of making nut'blanks, employing bar stock of the same cross sectional shape as that of the finished blank but of smaller cross sectional area.

' One of the objects of the invention is the provision of a method which shall permit the manufacture of blanks of a great many different sizes from bar stock of a few sizes onl i nother object is the provision of a method of making nut blanks inwhich the amount of scrap is relatively small, in fact confined to the stock lost in punching the hole in the blank. a A further object is the provision of a method in which the wear upon and breakage of tools shall be small.

Other objects and features of novelty will appear as we proceed with the description of the pr'ocedure'whioh, for the purposes of the presentapplication, is illustrated in the accompanying drawings,wherein V Figure 1 is a sideor plan view of a piece of hexagonal bar stock showing where the bar may be severed to provide a length of material for the making of a nut blank in accordance with the invention.

Fig. 2 is an end view of the same.

Fig. 3 is a fragmental view of a pair of anvils with a compressed length of stock therebetween, the original piece being indicated in the same view in dotted lines. Fig. 4 is an end view of the same.

.Fig. 5 is a diagrammatic, sectional view showing a blank that has been forced through a reducing die and has been pierced and crowned, togetherwith the dies and punches for accomplishing these operations.

Figs. 6 and 7 are edge and end views, respectively, ofthe blank at this stage of its manufacture.

Fig. 8 is a fragmental view, partly in section, of a blank compressed between a countersinking die and punch.

Fig. 9 is a similar view of a blank after it has passed through a second finishing die, showing the die and the punch, the latter having a pilot upon which the blank is supported and by which its hole is dimensioned;

1930. Serial No. 464,246.

Fig. 10 is an edge view of the finished blank.

Fig. 11 is a face view of the crowned side or end of the blank, and

Fig. 12 is a face view of the thereof.

It has been proposed at various times to manufacture nut blanks frombar stock by cutting therefrom lengths of stock somewhat in excess of the thickness of the desired blank, and compressing such lengths in'a confined space, so as to properly shape and dimension the blank. These'efiorts have met with some degree of success where the increase in lateral dimensions has been kept small, that is to say where the diameter has been increased a matter of thousandths of an inch. WVhere attempts have been made to increase lateral dimensions beyond approximately ten thousandths of an inch 'however very serious difficulties have been encountered, due to the fact that the stock when compressed does not move uniformly. One piece may go to the left, with respect to the center of the confined space, and the next may go toward the right or in some other direction, and in order toma'ke the stock fill .the confined space it becomes necessary to employ extremely high pressures. Such high pressures not only mean the waste of considerable power, but they are also highly detrimental to dies, resulting in frequent breakage of these costly tools.

In the present invention we have eliminated the confining of the stock during its longitudinal compression, permitting it to expand laterally in a natural way, thereby enabling the use of a minimum amount of power. The process starts with bar stock of square or hexagonal shape, to correspond with the shape of the desired blank. WVhen thestookis compressed it retains this form, except that the sides are bowed outwardly more or less, the amount of such bowing being dependent upon the extent of the compression. The compressed length of stock is then passed through a reducing die, the bowed walls facilitating this operation,'and thewrench facets of the blank are thus flattened and trued up. These are the essential steps of the method. The piercing of the eta 7 blank, the formation thereupon of a crown [and the production of countersinks therein maybe accomplished in Various ways, al-

though the preferred procedure is disclosed herein and will be referred to more particu- V tionofthe invention. I

In the drawings we have indicatedat. lO a bar of hexagonal stock such as we employ Q VVhereblanks of other shapes are desired,*the

bar stock employed will correspondinerosssection with the cross section o fthe blank; In Fig. 1 we have indicated atgllj aeut whichmay be made across the bar 10 in order such as maybe used in carrying out the further stepsof the methods; l-hislength of stock is then placed betweenflat faeed'anvils 13 and 14:,Fig. 3,- the'work surfia'ces'ofl-which are preferably slightly roughened in orde'r V to provide good frietionalcontact with the workand 'prevent slipping ormoving transversely. :The" original length of "stock vg 1 2is indicated in this-figure by dottedline's.

Brj-ess'ure is exertedto f cause the anvils 13 i and 14 to move-towardeach other to the posi- -1 tiom indicated in FigI'S, whereby thelength of st'oc'k 12 is compressedandthe stock -expended IateraII-ytohrm'the blanklii. This t1ank hasb weu walls and corners-as illustrated. The ani'ountf'=0fbowing f increases with-the amount of jcompre'ssion, and this eomp'ressioni; maybe any quantity. However, the original? length of thestock must not exceed three- 3 times its diameter, approxi- 'nratel-y; stock 'of greaten length is a'pt to 3 birckl e or'bend instea'd of being' merely comressed 'and'expandedilaterally. V 1 iTheneXt-step of the methods tolshape-the side walls ottheblankiby passing it through a reducing die 16, Fig. 5. This Inlay. be 1 a'c feomplish'ed .by means ota hollow punch. 17 which'fclosel-y -fitsi the: hole in? the exit. portion rot the die. Inthis :step of :the method the lwalls of the blank areiflattened trued up and dimensioned. :While wehave' termed the die 161areducing die, :it will be apparent that its tunetion is not alone reducing, as itactirally increases: the cross sectional-areal at thatface of the blank which :is last to enter the die. In other words-the excess" metal taken from .tlleiOlltwafdlyb owed portion; is driven hack itowstrai ghten up; the side walls oi the blank.

Hence thefunctionof the die is toreducer-the blank in its middle section and enlarge-.itiat one end-face. r Further'movement ofithehollow;1punch;17 may be caused to force-the blankalgainstv aicrowningdie 18,1 after wh-ich the mo vement of the punehil' l eeases" andthe movement of-a piercing pun'ch 19,=-sl ida'ble ,swithi'n the punch :17, I begins. j The forward i end of the piercing-punch l9 -enters" a* hole a o 201 m die 18', andthe slugs punched from th t1anks arenisehar ed firrough this ho ie.

larly as We proceed with .a detailed descrip 1 *for the 3 production of hexagonal -b1a1iks-.=,

to sever from the bar a length" of steak 12 When these operations are completed the blank takes the form illustrated at 21 in Figs. 6 and 7 that is to say it is crowned and pierced, but not countersunk. V o

The countersinking of both ends of the hole r may 'be accomplished by the means illustratedin 'Fi g. 8, wherein the:die 22 is formed with a concave surface 23 to receive the crowned surface of the blank and with a eone 24 whichacts to :"countersink one-"end of tlre hole in the blank. A'punch 25 'carry- ,ing a cone,projection.26 for forming the countersink on'tlie rear of the blank, cooper- Qates;with';the die;22in a manner which will beobvious to those skilled in the art. :Now, iiniorder "to" accurately-finish both f-the i exterior interior. surfaces of the blank, the i latter may 1 passed r'thro'u'gh a .finishin'gidie .27 zby means-tot Ia ipun'ch 28, 'upon the forwardrend ofwhichis a :p-i1ot 29 th'at-enters' thehole in the blank and forms arraccurate cylindrieah surface against which :the blariksisi compressed as it. passes through they die. At the base of the pilot 29 therezis a cone surface .30 which fits :the: countersink 12.90 in the corresponding face of the blank.

Thezfinished' blank-731' is V illustrated in Figs. .10, 1:1 andl1'2iof'the drawings, the 1 crowned end being shown in 11 and the rear end i-nllig. 172.2o r 7 In the method iwh ieh we :have iabove. described there is no waste material except-that lost by the; punching of the; holein the blank. Theblank *when rcompressedais unconfined, and hence there areno erielosing-diewalls to 23:00

be brokenf by,a excessive pressure. :Various V expedient-got varying, 5the length: 0f

severedirorh-the? bar-nndzkthe degree of; com- 1205 .pression of that: length. 1 By our method we are enabled to increase the crossrsectionalfarea of the stock asmirch-as-seyentypercent, and the increases will in; many Leases be above torty percent; ;;A s an f instance of what may 2110 'lbeadone wewmayi-mention- Ith at one-haltv inch stock maybe employed forltheimanufacture of fiveeightlrs ,i-neh, eleven sixteenths'l inch andthree fourths iinchv blanks. 'Whilein th foregoingdescription and in i the accompanying drawings we' haye disclosed more orless-jin-detail xone particular embodiment ,of the invention," we "desire it to be understood -that "such" damn disclosure has been resorted to-;prinrari ly'for "the-jpurr20 pose of fully illustrating the inyentionin compliance with the requirements or: the statute, sand that it is' not to heficonstrued as amounting to a limitation u 0n the-ss e of the invention. 7 r i V v E flaying thus described ourainvention, we mp, it 7. a a p j 1 .K'meth od oi making nut 'blanks"from c old stock', whi eh comprises aerating from a bar of polygonal.aeross section a:lngthof 1 stock, compressing said length endwise between fiat faced anvils without confining its side walls, whereby its side walls are bowed outwardly, and then pressing the blank through a reducing die of substantially the same shape as the original stock, and piercing it.

2. A method of making nut blanks, which comprises cutting from a bar of polygonal cross section a length of stock, compressing said length endwise between flat faced, rough surfaced anvils, whereby its side walls are bowed outwardly and then pressing the blanks through a reducing die of substantially the same shape as the original stock, and piercing it.

3. A method of making nut blanks, which comprises cutting from a bar of given polygonal cross section a length of stock greater than the thickness of the desired blank, compressing said length endwise between parallel fiat surfaces without confining the side surfaces of the stock until the desired transverse dimensions are reached approximately, the sides of the blank being bowed outwardly thereby and then forcing the blank through a reducing die of substantially the same shape as the original stock but of larger size, and piercing it.

4. A method of making nut blanks, which comprises cutting from a bar of polygonal cross section stock materially exceeding in length the thickness of the desired blank, expanding said stock laterally by compressing it endwise between flat faced anvils, whereby its side walls are bowed outwardly and then pressing the blank through a reducing die of the same shape as the original stock but of greater size, and piercing the blank.

5. A method of making nut blanks which consists in cutting from a bar of polygonal cross section stock of a maximum length of three times its diameter, expanding said stock laterally in all directions by compressing it endwise between flat faced anvils, whereby its side walls are bowed outwardly and then pressing the blank through a reducing die of the same shape as but greater size than the original stock, and piercing the blank.

6. A method of making nut blanks which 7 comprises cutting from a bar of polygonal cross section stock of a predetermined length, expanding said length laterally by compressing it endwise between flat faced anvils, whereby the wrench facets are bowed outwardly, and flattening the wrench facets by forcing the blank through a reducing die.

7. A method of making nut blanks which comprises cutting from a bar of polygonal cross section stock of a predetermined length, expanding said length laterally by compressing it endwise between flat faced anvils, whereby the wrench facets are bowed outwardly, and flattening, truing up and diour signatures.

LEE A. FRAYER. CARL L. HARVEY. 

